The Study On The Preparation And Properties Of Starch-based Biomass Foaming Composites

Non-biodegradable foaming plastics take greatly convenience to our lives,but also bring the problem of pollution to the environment caused by the production,which is increasingly serious.To solve this problem,the starch-based biomass foam composite material was prepared by extrusion foaming in this paper,which is a completely biodegradable foam.But some issues of this material,such as poor water resistance,high density,the spring rate is not high and the number of cells less uneven distribution were still existed.To solve these problems,the action mechanism of this material aids,the extrusion foaming simulation,the effect of relevant factors to its performance?such as foaming properties,mechanical properties,melt viscosity?and the microstructure were focused research in this paper.The results showed that:?1?The extrusion foaming simulation model can effectively predict the rate and density of the foam bubble.?2?When the addition of cassava starch,glycerol/NaOH composite plasticizers,NaHCO₃ foaming agent and PVA were 55 phr,20phr,2phr,20 phr,6phr,the density of the material had a minimum,but the spring rate was maximum.?3?When the added amount of the plasticizer composite was 20 phr,the maximum tensile strength was 11.2MPa;when the addition of borax was 2phr,the maximum elongation at break was 85%;the influence of the inside and outside lubricant of stearic acid?HSt?/ polyethylene wax?PEW?composite on the mechanical properties of the materials was significantly improved;the nucleating agents,coupling agents could significantly improve the tensile strength,flexural strength and impact strength,which the obvious enhance effect was ordered by: activity of calcium carbonate > precipitated calcium carbonate > heavy calcium carbonate,aluminum titanium composite coupling agent > aluminum coupling agent > silane coupling agent.?4?The relative factors affected the melt viscosity was ordered by strength and tendency: amount of starch > shear rate > NaHCO₃ added amount > Temperature > glycerol/NaOH composite plasticizer addition.?5?The processing properties of the wood flour fiber thermoplastic treated by the 4% NaOH solution was much better;when the wood flour mesh was 80 mesh,the amount of blowing agent of NaHCO₃ was 2phr,and the melt viscosity at 1600 Pa·s,a larger number of and more micromesh cell bubbles were obtained in the composite.?6?When the amount of the plasticizer composite was 20 phr,flour amount of fiber was 6phr,preferably degradable properties of the material was obtained,and the weight loss rate was about 40%.